Most engine blocks include a cooling system. Conventional engine cooling systems include engine coolant to control the temperature of the block and other engine components. In cold temperatures, the cooling system heats the block. In hot temperatures, the cooling system cools the block. Typically, the engine block includes channels, commonly referred to as water jackets, for circulating the engine coolant about the block.
In the past, engine blocks having water jackets have been manufactured primarily in two types of designs. A first type of engine block has an open top. That is, the block is manufactured with water jackets located between the walls of each cylinder and the adjacent outer walls of the engine block. This type of engine block is commonly referred to as an open deck engine block. Open deck engine blocks have several shortcomings. Foremost, the top of such blocks lack rigidity and, therefore, sometimes warp either initially during the manufacture of the engine or later during the operation of the engine.
To overcome this shortcoming, a second type of engine block has a partially closed top or deck. This engine block has been manufactured as a single piece block. Unlike the first design, this second type of engine block includes support material diecast between a portion of the cylinder wall and the adjacent outer engine block walls. The support material improves the rigidity of the top of the engine block yet does not significantly restrict coolant flow between the engine block and the other engine components. However, this second type of engine block also has several shortcomings. Foremost, temporary sand molds are required to manufacture this type of engine block as a single piece. Frequently, residual sand from the casting process damages tools used to machine the block. Accordingly, it would be desirable to provide an engine block having water jackets manufactured from only permanent molds.